Converting compose file fails with "invalid start character `~`" or "external networks (`proximity`) are not supported"

I wanted to convert a quite simple podman compose file:
```
---
name: searxng
services:
redis:
container_name: redis
image: docker.io/valkey/valkey:8-alpine
command: valkey-server --save 30 1 --loglevel warning
restart: unless-stopped
networks:
- searxng
volumes:
- ~/volumes/searxng/valkey-data2:/data
cap_drop:
- ALL
cap_add:
- SETGID
- SETUID
- DAC_OVERRIDE
logging:
driver: "json-file"
options:
max-size: "1m"
max-file: "1"

searxng:
container_name: searxng
image: docker.io/searxng/searxng:latest
restart: unless-stopped
security_opt:
- label:disable
networks:
- searxng
- proximity
expose:
- 8080
volumes:
- ~/volumes/searxng:/etc/searxng:rw
environment:
- SEARXNG_BASE_URL=https://${SEARXNG_HOSTNAME:-localhost}/
- UWSGI_WORKERS=${SEARXNG_UWSGI_WORKERS:-4}
- UWSGI_THREADS=${SEARXNG_UWSGI_THREADS:-4}
cap_drop:
- ALL
cap_add:
- CHOWN
- SETGID
- SETUID
logging:
driver: "json-file"
options:
max-size: "1m"
max-file: "1"

networks:
searxng:
proximity:
external: true

volumes:
valkey-data2:
```

`podlet compose --pod` gives me this error:
```
Error:
0: error converting compose file
1: error reading compose file
2: File `docker-compose.yaml` is not a valid compose file
3: services.redis.volumes[0]: error parsing volume source: error parsing volume identifier: invalid start character `~`, identifiers must start with an ASCII letter (a-z, A-Z) or digit (0-9) at line 14 column 9

Location:
src/cli/compose.rs:203

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ BACKTRACE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
1: __libc_start_call_main
at :
2: __libc_start_main@GLIBC_2.2.5
at :

Run with COLORBT_SHOW_HIDDEN=1 environment variable to disable frame filtering.
Run with RUST_BACKTRACE=full to include source snippets.
```
If I remove the trailing "~" just for testing, I get this error:
```
Error:
0: error converting compose file
1: error converting compose file into Quadlet files
2: external networks (`proximity`) are not supported

Location:
src/cli/compose.rs:384

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ BACKTRACE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
1: __libc_start_call_main
at :
2: __libc_start_main@GLIBC_2.2.5
at :

Run with COLORBT_SHOW_HIDDEN=1 environment variable to disable frame filtering.
Run with RUST_BACKTRACE=full to include source snippets.
```